Motor speed control apparatus



May 24, 1932.

J. I. HULL MOTOR SPEED CONTROL APPARATUS I5 Sheets-Sheet 1 Filed May 17,1939 FQZ.

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Inventor-z John I. Ilul l.

H is Attorney.

May 24, 1932- J. a. HULL uo'roa SPEED CONTROL APPARATUS Filed May 17,1930 3 Sheets-Sheet 2 II II Fig.4.

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May 24', 1932. Jfl. HULL MOTOR SPEED CONTROL APPARATUS Filed May 17,1950 3 Sheets-Sheet 3 0 I. V. A I e wi y Z14 .515 9 a. a a n m '8 n h Fm a v//%// a .l. o E 0 .YJ H m a. y. g fi 6 Union, 5 a. Q :lm F a l fl MM w w Patented May 24, 1 932 UNITED STATES PATENT ori-."icr

JOHN I. HULL, OFSCHEN 'ECTADY, NEW YORK, ASSIGNOR T GENERAL ELECTRICCOM- PANY, A CORPORATION OF NEW YORK MOTOR SPEED UONTRO'L APPARATUSApplication filed Kay 1?, i930. Eerial No. 58,339.

5 machines and the like.

The principal object of my invention is to provide a controller whichwill receive at least one motion from a moving element on the spinningmachine, transfer this motion to a movable controller member and convertthe motion of this member to a regulating motion having suchcharacteristics that its application to the speed adjusting means suchas the brush shifting device of the spinning machine motor causes themotor speed to vary'in a substantially constant ratio to the movement ofthe controller member.

Another important object of my invention is to'provide a. controller foroperating the brush shifting device of the spinning machine motor insuch a manner that the speed of the spinning machine is varied in apredetermined manner according to the position of the yarn on thebobbin.

An additional object of my invention is to provide the controller withadjusting devices whereby the s inning machine can be operated withdiflgrent forms of spinning cycles to suit var'yin qualities of yarn,varying degrees of humi ity, etc. without requiring the interchange ofnew parts or requiring more knowledge than is possessed by the averageoperator. A further ob'ect of my invention is to provide a brushshifting device for the spinning machine motor which will act inconjunction with the controller to produce the desired speed variationsin the spinning machine, the brush shifting device and controller to beso constructed that the brush shifting device can be moved to atemporary position independently of the controller position so as tostart the motor with minimum starting current and after the motor hasaccelerated the brush shifting device may he returned to the positiondetermined by the controller. An additional object of my in vention isto provide means for shifting the brushes to obtain desirable motoroperating characteristics with either direction or retation and meansthat will automatically cause the motor to run in that direction ofrotation for which the shifting of its brushes ives desirable operatingcharacteristics. ther objects of my invention will become evident asthis specification progresses.

I prefer to describe my invention in connection With a ring spinningmachine driven by a brush shifting alternating current motor because ofthe-relatively large number of ring spinnin machines as compared toother types, t e peculiar spinning cycles required by ring spinningmachines and the prevalence of alternating current as a supply source,but it will be evident that my invention can be applied to other typesof motors and'textile machinery with beneficial results.

-'lhe operation of my invention with its resuiting advantages will bebest understood from the following description when considered inconnection with the accompanying drawings. 1 have not illustrated anyparts of spinning machines since they are old and well known to thoseskilled in the art and my invention does not depend on their particularconstruction. In order to assist in the description of my invention 1will refer to that portion of the spinning machine which causes thereciprocating motion of the ring rail as the traverse mechanism and thatportion which causes the advancement of the ring rail as the buildermechanism. The features of my invention which are believed to be noveland patentable will be pointed out in the claims appended hereto.

Fig. 1 represents an ideal filling wind spinning cycle of a rail ringspinning machine. Fig. 2 represents comparative curves showin tr erelation between the controller receive motion and the resulting speedchanges of the spinning machine with my controller and the usual type ofcontroller. Fig. 3 represents part of my controller mecln anism andbrush shitting device in a simplilied form so as to more readilydescribe how I produce speed changes which have a substantially constantratio to the controher received motion and how I may vary ratio. Fig. irep-resents pers ective view or my controller and brush shitting device.Fig. 5 represents the electrical connections of the motor in conjunctionwith means to automatically cause the motor to rotate in the desireddirection with improved operating characteristics/ Fig. 6 represents anenlarged detail drawing of that portion of the controller which convertsthe controller received motion into the controller regulating motion tobe applied to the brush shifting:

device and this figure also shows the means for changing the ratio ofthese two motions. Fig. 7 represents a top sectional view of theassembly of the shifting yoke and movable brush yokes of the drivingmotor together with the means used to prevent appreciable friction ormisalignment during the movements of the brush yokes. 8 represents anenlarged detail drawing of the means used to guide the operating yoke ofthe brush shifting mechanism in the desired manner. Fig. 9 represents anenlarged detail drawing of a preferred form of coupling used between thetraverse cam of the controller and the traverse mechanism on thespinning machine. Fig. 10 represents a preferred form of locking meansused to prevent vibration and similar'forces from changing therelative'position of two of the controller members.

In Fig. 1 the abscissa represents the time required for winding onebobbin, the exact time being omitted as immaterial for our discussion,and the ordinate represents spinning machine speeds and therefore alsorepresents bobbin speeds as the bobbins are driven at speeds directlyproportional to the speed of the spinning machine. The usual spinningmachine is operated at a constant speed whose value is such that'theyarn tension never exceeds a permissible value. Thus if, during thewinding of the bobbin, A represents the speed during some part of thespinning cycle which cannot be exceeded without excessive Y yarntension, then a constant speedspinning machine should not be operated inexcess of the speed represented by A and the production is proportionalto' the area included under A. The yarn tension varies when the spinningmachine is driven at constant speed and it has long been recognized thatboth production and quality of yarn can be improved by driving thespinning machine at varying speeds to result in a substantially constantyarn tension during the spinning and this requires the idealspinningspeed cycle shown for example by the full line curves in Fig. 1.Both theory and experiments indicate that to operate in accordance withthe ideal spinning cycle the spinning machine should be operated at asubstantially constant speed during a part of the formation of theconical base as for example represented by the speed A during the regionB. During the formation of the remainder of the conical base re resentedby C the speed is raised and lower with each layer, the maximum speedbeing increased with each layer but the minimum speed remaining) at A,the operating speeds being shown the full nes S. After the completion 0the conical base the speeds are raised and lowered with each representedby F it is usually desirable to raise and lower the speed with eachlayer and also gradually reduce the maximum speeds without materiallyalterin the speedvariation per layer, these speeds eing represented byS. The increased production is represented by the area included betweenthe dotted ortion of A and the full line curves S S 5 and S. It isevident however that varying qualities of yarn, varying degrees ofhumidity, etc., require various forms of spinning cycles to obtain theideal spinning cycle for the particular 0 erating condition, and thus itbecame desira le to devise a controller provided with means. for quicklychanging any or all portions of the spinning cycle without requiring theinterchange of new parts and consequent interruption of operation andwithout requiring more knowledge than is possessed b the averageoperator. Various controllers ave been deent operating conditionswithout the interchange of new parts.

Additional reasons why heretofore built speed control devices did notaccomplish the desired results is the fact that they mostly centeredaround the use of a controller for shifting the brushes of a seriescharacteristics alternating current motor without giving attention tothe relation between the controller moi'ement and the resulting speedchanges. The speed changes *of the series characteristics motor are notstrictly proportional to the brush shift and since different relativebrush positions are necessary when the spinning cycles are changed fordifferent operating conditions it was not possible to obtain idealspinning cycles with difi'erent operating conditions .unless thecontroller parts were changed. In addition, when compared to the shuntcharacteristics alternating current motor, the speed of the seriescharacteristics alternating current motor changes more for a givenchange of voltage or friction in the spinning machine and also it takesmore time to make a given change in speed, thus tending to decreaseproduction and quality. This question of production is so important thatmany mills keep a graphic chart of the speed and it therefore becamedesirable to provide a drive which avoidsthe above describeddisadvantages. I, therefore, prefer to use a shunt characteristics brushshifting alternating current motor, such as is described in ReissuePatent No. 14,031, Schrage, Dec. 14, 1915, and in addition I provide acontroller which shifts the brushes in such a manner as to secure speedchanges which have a substantially constant ratio with the resultantreceived motion imparted to the controller from the spinning machine.

'lhe usual Schrage motor consists of a rotatin g primary windingconnected to the supply source and a rotating commutated winding onWhose commutator rest movable brushes and stationary secondary windingshaving the ends of each phase connected to the commutator brushes. It iscustomary to change the speed of the motor by shifting the brushes inopposite directions at equal or nearly equal speeds. I will assume forexample that the motions imparted tothe controller by the spinningmachine give a controller received motion of 9 inches which is capableof shifting the brushes 180 electrical degrees and that synchronousspeed represented by J occurs at the center of this'movement as shown inFig. 2. It follows that a movement of the controller of 4.5 inches inone direction from center or synchronous speed position shifts thebrushes 90 electrical degrees to give minimum speed below synchronism asshown by J, Whereas a movement of 4.5 inches in the opposite directionshifts the brushes 90 electrical degrees to give maximum speed abovsynchronism as shown by J". H the controller received motion is impartedto the brush shifting device so that the angular shift of the brushes isproportional to the .controller received motion, then GG would representthe relation between the brush shift and the controller received motion,and the relation between the motor speed and the controller receivedmotion will be represented by the portions of the sine curve HH, becausethe speed change of the Schrage motor is substantially proportional tothe sine of the brush shift angle from synchronous speed position. Ifthe controller received motion is converted into a controller regulatingmotion whose relation to the controller received motion is representedby the portions of the sine curves KK, then the relation between thespccdand the controller received motion will be represented by thestraight line GG. This relationship results in the smallest brush shiftangle for a given controller received motion at synchronous speed andthe largmt brush shift angle for a given controller motion at maximumand minimum speeds. Thus I aim to obtain speed changes havin asubstantially constant ratio to the control er received motion whichresults in uniform operating conditions.

In Fig. 3 I have represented parts of my controller and brush shiftingmechanism in simplified form to better show how I obtain this constantratio and how I can change its numerical value. In Fig. 3, L representsthe operating member to which is imparted the resultant receivedcontroller motion and which can move only in a vertical direction; Mrepresents a gear on which is mounted a roller N which is adjustable asto its distance from the center of the gear; P represents a. rack inmesh with the gear and P has an antifriction roller R in contact withthe shifting yoke S which moves the brush yokes T by the driving pins U,thus shifting the brushes V upward around the commutator W, whereastheir movement downward is brought about by gravity when P movesdownward. sume that when L is at the position [a as shown in Fig. 3, itcorresponds to the brush position resulting in synchronous speed andthat the movement of L from A to D corresponds to that half of itstravel which re sults in operation below synchronous speed.

Let us space AD into three equal parts as shown and assume the roller Nat the position E. It can be seen that the movement of L from A to B, toC and to D will result in corresponding positions of the roller N at F,G and H, thus resulting in angular movements of N corresponding to l, Jand K. The angle K is larger than the angle J which in.

turn is larger thanthe angle I and ifthe,

vertical motions of L is plotted as the ordinates against the angularmotions of N as abscissa, the relation will be represented by a. sinecurve since the vertical motion of L is equal to the vertical motion ofN and is therefore proportional to the sine of the angular motions of N.As P meshes with M it follows that the same relation will exist betweenthe motion of P and the vertical motion of L. In operation the brushyokes are seldom moved more than 30 mechanical degrees from synchronousspeed position to give maximum or minimum speeds and thus the angularmovements of the brushes will be substantially proportional to themotion of P. As the smallest angular motion of N for a given motion of Loccurs at synchronous speed, it follows that the relation between thebrush shift angle and the motion of L will be represented by KK in Fig.2 and thus the relation between the motor speed and the motion of L willbe represented by GG in Fig. 2. it is evident that the same will be truewhen [asa If the roller N is moved inward, as for example to E, themovement of L from A to B, to C and to D will result in correspondingpositions of the roller N at F, G and H and angular motions of Ncorresponding to I, J and K. The angle K is larger than the angle Jwhich in turn is larger than the angle I, but the angles K, J and I arelarger than the corresponding angles K, J and I. The relation betweenthe motions of P and L will be the same as with the roller N at E butthe ratio of their motions will be greater and therefore a greater speedchange will result for the same given motion of L assumed with theroller N at E. If the roller N is moved outward to the position E, therelation between the motions of and L will remain unchanged but theratio of their motions will be decreased from the ratio existing withthe roller N at E and thus a smaller speed change will result for thesame given motion of L assumed with the roller N at E.

Having outlined the basic principles of my invention in so far as. theyrelate to the controller T will now describe a preferred construction ofmy controller and brush shifting device and their operation.

In Fig. 4, 10 represents the traverse cam receiving its motion from thetraverse mechanism of the spinning machine through the coupling 11 andthe shaft 12 which is connected to the traverse mechanism of thespinning machine, whereas 13 represents the builder cam receiving itsmotion from the builder mechanism of the spinning machine through theshaft shown protruding through this cam, which shaft is driven by thepulley 14 to which the cable 15 is fastened by the pin 16, one end ofthe cable 15 being connected to the builder mechanism and the other endbeing connected to one end of the spring 17 which has the other endfastened to some stationary point. The beams 18 and 19 respectivelycarry the rollers 20 and 21 engaging the contours of the cams 10 and 13respectively. The beams 18 and 19 are pivoted in each other by thefulcrum block 22. A pin 23 is fastened to the beams 18 and a spring 24is fastened between the pin 23 and the bent down ends of the beams 19 soas to always be in tension and it is evident that as the cams 10 and 13rotate the beams 18 and 19 will move as a unit because the tension ofthe spring 24 always keeps the upper edges of the beams 19 against thepin 23.

Although illustrated in Fig. 4, the following parts will be betterdescribed and understood from the detail drawing Fig. 6 in which it canbe seen that the fulcrum block 26 is pivoted in notches on the upperedges of the beams 18. The screw 25 has a shoulder 25 of which one facerests on 26 and the gear 27 assembled on the end of 25 rests against theother face of the shoulder 25'. The screw 25 projects through the holein 26 with a slight clearance and the lower end of 25 is threaded intothe operating member 28. A bolt 29 is screwed into the internal threadof the screw 25 and a nut 30 locks both 27 and 29 to 25. The operatingmember 28 is permitted tomove vertically only because it slides on thevertical stationary shaft 31 which has a slot 32 in which slides the pin33, thus preventing circular movement of 28 around 31. 28 engages aroller 34 mounted on the block 35 of which one face rests against thegear 36 in mesh with the rack 37 which can move vertically only becauseit has a slot fitting the tongue of the vertical stationary part 37'.The principles of operation and the results obtained as, discussed inconnection with Fig. 3 also apply to 6 because in Figs. 3 and 6 thefollowing parts respectively correspond, L and 28, M and 36, N and 34, Pand 37. During operation it is necessary that 35 and 36 rotate as a unitso that movement of 34 causes movement of 36 and vice versa, but itshould also be possible to change-the distance between the centers of 34and 36 without permitting vibration and similar forces from effectingsuch change. These results are accomplished in the following manner. Asmore clearly shown in Fig. 4, the slot in the block 35 fits over theangle piece 38 fastened to 36 by rivets 39. eferring again to Fig. 6,the stationary pin 40 has a shoulder 41 and on the small end of 40 thereis a loose sleeve 42 welded to a handle 43 which is near the other faceof 35. A bolt 44 is threaded into the small end of 40 and the sleeve 42fits between the shoulder 41 and the head of bolt 44 with a very slightclearance. The sleeve 42 has an external thread. fitting into a similarinternal thread in the gear 36 and assuming these as right-hand threadsit can be seen that moving 43 clockwise rotates 42 which can moveaxially only its clearance, thus causing 36 to advance on the thread of42 until 35, 36 and 43 are tighten-ed together so as to move as a unit,and to free 35 from 36 it is merely necessary to move 43counterclockwise. To change the distance between the centers of 34 and36 there is threaded into 35 a screw 45 having a shoulder and a smallend to which is fastened the knurled wheel 46 having another shoulder,the two shoulders being on opposite sides of 38 so that turning 46changes the distance between the centers of 34 and 36 means thus I canadjust the relative positions of 25 and 28. On the rack 37 there ismounted an anti-friction roller on which rests the opcrating yoke 51having two bosses 52 on which rest driving pins 53 fastened tobrush okes54 and 5,5. The yoke 54 carries the rush holders and brushes 56, 56' and56" and also the lug 57 for closing the switch blade 58 against thecompression spring 59 and thus short circuit the contacts 60 when 54reaches a predetermined osition. The yoke 55 carries the brush hol ersand brushes 61, 61 and 61" and the lug 62 for closing the switch blade63 against the compression spring 64 and thus short circuit the contacts65 when 55 reaches a predetermined position. The plate 66 is fastened tothe motor housing by three bolts 67threaded into the housing and passingthrough clearance holes in the plate 66. The purpose of the three jackscrews 68 will be described later. The boss 69 on the plate 66 limitsthe upward travel of 28 and 29. The hubs of the brush yokes 54 and 55slide around a machined surface on the motor housing while the operatinyoke 51 has an opening 7 0' whose-two parallel faces slide on theoutside diameter of the hub of brush yoke 54, the length of 70 beinggreater than its width so as to permit 51 to move radially and angularlyand retain contact with the hub of 54. The operating yoke 51 has, anelongated slot 71 through which protrude two bolts 72 threaded into theplate 73 and on the ends of these bolts there are rollers 74 in contactwith the contour of the cam plate 75 fastened to the stationary boss 76by a bolt 77. The cam 75 has a slot 78 which fits over a stationary pinthus makin 75 rigid and to the top of 75 there is secured a plate 79 bymeans of bolt 80. The plate 79 is secured to the motor housing by bolt81 and the plate 79 has an additional bolt hole 82, two elongated slots83 and 84 and two stamped arrow marks. To the operating yoke 51 there isfastened a clevis 85 to which is secured a rod 86 on which there isscrewed the knob 87.

The assembly of the yokes 51, 54 and 55 and the plate 66 are moreclearly shown in Fig. 7 in which similar parts to those shown in Fig. 4are represented by the same numhers,- the additional parts ing the motorhousing 88 and the commutator 89. It can be seen that the operating yoke51 slides on the outside hub diameter of brush yoke 54'whereas brushyokes 54 and 55 slide on the finished jecting hub and by moderatelsurface of the motor housin It is very important that these three yo es0 rate with practically no axial clearances an slide with negligiblefriction because friction will cause 'sluggishresponse to required speedchanges in'the motor with resulting imperfect spimng cycles whereasnoticeable axial clearances results in tilting ofthe yokes with harmfuleffects on speed and power factor, regulation. The internal hubdiameters of the yokes are made appreciably larger than thecorresponding housing diameters, thus eliminating friction from thosesurfaces and no harm results from these clearances because gravityalways keeps those clearances at the bottom. It is desirable tomanufacture these yokes and housin s without resorting to smalltolerances in t e m'achinin of the housing and yokes and quicklyassemble the yokes on the housing without appreciable axial clearancesand without appreciable friction in the movements of the yokes. Theseresults are obtained by making the combined width of the hubs of brushyokes 54 and 55 such that when the hub of 54 rests against the shoulderon the housing 88 the hub of 55 will project slightly beyond the end ofthe housing. The plate 66 will rest against the face of theprotightening the bolts 67 which fasten the p ate 66 to the housing 88the plate 66 will bear with'even tension against the hub face of yoke55. The three jacking screws 68 are threaded into the plate 66 and theirends rest against the housing 88 and by tightening the screws 68 againstthe housing 88 I remove the tension existing between the plate 66 andthe hub of yoke 55 without any noticeable axial clearances.

A clearer understanding of the mechanism used for guiding the shiftingyoke 51 may be obtained by examinat-ing Figs. 4 and 8 togather, thesimilar parts in both figures being represented by the same numbers. InFig. 8 it can be seen that the slot 78 of the cam 75 fits over the pin90 and the bolts 72 are threaded into the plate 73 whose threaded holesare so spaced that the rollers 74 assembled on the ends of bolts 72 willroll along the contour of the cam 75 without appreciable friction. 91represents cotter pins to retain the rollers 74 in place.

A clearer understanding of the operation of the controller and brushshifting device will be obtained whenl'their operation is describedin-conn'ection with both Figs. 4 and 5 and therefore I will now describeFi 5 in, which similar parts to those shown in ig..-4- are representedby the same numbers. In-

nected a} the rotatable commutator 89 .n

which rest' the brushes as shown. The

brushes are connected'to a preferably station- ;ary secondary winding101. I have assumed a two-pole machine with the commutator brushes inthe ppfition corresponding to maximum speed a ve synchronism andtherefore I have represented the ends of each secondary phaseconnectedto brushes separated 180 mechanical degrees The switches 97 and98 are respectively operated by solenoids 102 and 103 the movable coresof which respectively carry contact making strips 104 and 105. Theremote control-switches 106 and 107' have stop push buttons 108 and 108which normall short circuit the contacts 109 and 109' ue to the tensionof springs 110. The solenoidgswitch 102 has holding.

contacts 111 and positive interlocking contacts 112 and either of thesecontacts may be closed by the strip 104. The solenoid switch 103 hasholding contacts 113 and positive interlocking contacts 114 and eitherof these contacts may be closed by the strip 105.

The followin description of the operation of the brush shifting deviceis to be considered in connection with Figs. 4 and 5. In acopending aplication Serial No. 410,197, assigned to t esame assignee of thisinvention, I have fully described the underlying rinciples for shiftingthe commutatorthe pins 53 when the rollers 74 res ctively operate overthe sections X and Z w ich will hereinafter be referred to as radialsections. The section Y is the arc of a circle whose center is the pin53 fastened to the brush yoke 55 :when the positions of the brush yokes54 and 55 correspond to approximately synchronous motor speed. Thesection Y will hereinafter be referred to as the circular section since1n theory it should be circular in form although in practice it mayvary. somewhat from t e circular form. I have assumed that the section Xcorresponds to supersynchronous operation and therefore the cam 75 issopositioned that when the rollers 74 o erate over the section X thevoltage injected y the commutated windin windings 101 wil have a speedregulating component and possibly a slight power factor correcting 'comonentsince with operation above synchromsm the motor ower factor isinherently high. To obtain the proper volta components with variationsin the me c anical structure of the yokes 51,54 and 55 100 into thesecondary.

and variations in the windings 100 m1 01,". I have provided the slot 71so that the brush axis may be shifted in its relation to the axis of thewinding 101. It is evident that when the rollers 74 operate overthe-section X the brush yokes 54 and 55 will be shifted in oppositedirections at substantially equal ve ocities and there will be goodmotor powerfactor with speed re llationabove synchronism. Sufiicientupwa movement'of 51 causes the rollers 74 to move to the section Y andduring operation overthis section the brush yoke 55 remains stationarysince'the section Y is the arc of a circle whose center is the pin 53fastened to 55 but the oke 54 moves at substantially double the ve ocitit would have if both yokes 54 and 55 move because the motion impartedto 51 is substantially half way between the ins53 and one of these pinsis stationary. it-h operation. over the section Y. the motor will run atapproximately synchronous speed and the total brush shift and hence thechan in s d for a given movement of 51'wilI be su tantially the same aswith operation over the sectionX, thus not disturbing the relationbetween the movement of 51 and the resulting speed change and alsoserving to quickly establish a power factor correcting brush axis foroperation over the section Z-which corresponds to: sub- ;synchronousoperation with lower inherent power factor. When the roller" 74 operatesover the section Z the brush okes 54 and Y55 will be shifted in o positedirections at substantially equal ve ocities with good motor powerfactor and speed regulations below synchronism.

Assume the controller and brush shifting device to be in the positionsshown in Fig. 4. To start the, motor 92 the switch 99 is closed and theoke '51 pulled up by the knob 87..

The brus yokes 54 and 55 will be brou ht to their minimum speed positionand t ey will be so guided that the yoke 54 will be higher than the yoke55 thus causing the lug 57 to close the switch blade 58 which com pletesthe circuit from the-source 94 through the contacts 60, 109 and 114 andthe solenoid 102, thus energizing 102 and closing the switch 97.Assuming correct connections to the brushes 96the motor 92 will start inthe direction for which the position of the cam plate 7 5gives goodpower factor and I have for example represented that rotation by thearrows. stamped on 79. It is evident that the motor is started with theminimum starting current and without disturbing the position of the rack37. When the motor has sufiiciently accelerated the yoke 51 is loweredso it again rests on the roller 50 and although the lowering of the yoke54 opens the contacts 60 the motor continues to run because when thesolenoid 102 closed. the switch 97 the strip 104 short circuited thecontacts 111 I and the solenoid 102 remains energized through thecontacts 109, 111 and 114.

Itis'often required to spin the yarn with a reverse twist andthereforeit is desirable to provide means that will shift the axis ofthe commutator brushes so as to give good power factor in the reversedirection of motor rotation and simultaneously bring about this reversedrotation and thus the motor would always run with a good power factor.To accomplish these results the knob 87 and the bolts 77 and 81 areremoved and the cam 75 is slid upwards so that its slot 78 is disenga edfrom the pin 90 (see Fig. 8). The cam 75 isthen turned 180 degrees andreassembled with the slot 78 again engaging the pin 90, the cam 75 isfastened to the boss 76 with the bolt 77 threadedinto the other hole onthe boss 76, the plate 79 is fastened to the housing by the bolt 81utilizing the bolt hole 82, the rod 86 now protrudes through the slot 84and the knob 87 is reassem led on 86. Assumin the switch 99 closed themotor 92 is started by pulling the yoke 51 up) by the knob 87 and it isobvious that the rush yokes 54 and 55 will be brought to their minimumspeed position and they will be so guided that 55 is higher than 54 thuscausing the la 62 to close the switch-blade 63 which comp etes thecircuit from the source 94 through the contacts 65, 109' and 112 and thesolenoid 103, thus energizing 103 and closing the switch 98. By tracinout the connections it will be seen that two 0 the leads from the-source94 to the brushes 96 have been interchanged and thus the motor willstart in the reverse direction which will be correctly shown by thereversed positions of the arrows on the plate 79. It is evident that themotor Willbe started without disturbing the position of the rack 37 andwhen the motor has sufficiently accelerated the oke 51 is lowered so itagain rests on the rol er and although the lowering of the yoke opensthe contacts the motor continues to run because when the solenoid 103closed the switch 98 the strip 105 short circuited the contacts 113 andthe solenoid 103 remains energized through the contacts 109', 113 and112. The new position of the cam plate 75 is such that its section Y isthe arc of a circle whose center is the pin 53 fastened to the brushyoke 54 when the position of the yokes 54 and 55 correspond to ap)roximately synchronous speed and this shi t in brush axis causes themotor to operate with good power factor in the reversed direction ofrotation. When running in either direction the motor can be shut downthe appropriate stoppush button 108 or 108' or by operating somearrangement which opens both push buttons at once. The purpose of thepositive interlocking contacts 112 and 114 is to prevent the closing ofswitch by opening switch. 99 or by operating 98 unless switch is openand vice versa,

-' because should both switches be closed at the The followingdescription of the operation of the controller is to be considered inconnection with Figs. 1 and 4. The cam 10 makes one revolution for eachlayer of yarn on the bobbin and the cam 13 makes slightly less than onerevolution for the entire spinning'cycle. The movements of the cams 10and 13 are combined into a resultant received motion which raises andlowers 28 and 29. The yokes 51, 54 and 55 are so positioned that theirweight tends to move them downward. The raising of 28 raises 34 thusrotatin 35 and 36 clockwise and raising 37 and 51 which results inshifting the brush yokes 54 and 55 upward, whereas the lowering of 28permits gravity to move the yokes 51, 54 and 55 downward, thus causing37 to move downward and rotate 35 and 36 counterclockwise and therefore51 is always in contact with 50 and 34 is always in contact with 28. Itis therefore evident that there will be no lost motion in the e eration'of the controller or brush shifting evice, thus resulting in consistentand satisfactory o eration over long periods of usage. I pre ertodescribe the motion of 37 as the regulating motion since it is themotion which is finally applied to 51 and from the descriptionsaccompanying Figs. 2 and 3 it will be evident that the controllerreceived motion of 28 is converted into a controller regulatingmotionol'- 37' which will be substantially pro'portional'to that anglewhose sine is proportional to the motion of 28in accordance with theprinciples discussed in connection with Fig. 3. The expressed-relationsbetween the motions of 28 and 37 will be unaffected by the shape of thecams 10 and 13, the direction of speed. .of rotation of the cams 10 and13 or the position of the roller 34. If it is desired to regulate themotor speed only in:response to the motion of the spinning machinetraverse mechanism this may be obtained by having cam 13 stationary orby having 13 circular in form and allowing it to rotate, whereas if'itis desired to regulate the motor'speed only in response to the motionof-the spin ning machine builder mechanism this may be obtained byhaving cam 10 stationary or by having 10 circular in form and allowingit to rotate. ceived motion will be represented by the motion of 28 andthe expressed relation between the motions of 28 and 37 will'beunaffected.

. The following serves to describe the controller operation during theideal spinning verse and builder mechanism of the spinning In all casesthe controller rehand wheel 49 to a slightly greater extent than isnecessary to maintain it in contact with 69 during the rotation of thecam 10 and the motor being properly adjusted will operate at the speed Abecause during the range B the rotation of the cam 10 and the gradualmovement of 13 results in no movement of 28 and thus no shifting of theyokes 54 and 55. No damage to the controller parts will result from thisstationary position of 28 because while those ends of the beams 18 and19 which carry the rollers 20-and 21 are moved upward the other ends ofthe beams are depressed as they swing around the folcrum blocks 22 and26, thus extending the spring 24 which serves to retain the unity of thecontroller. As the spinning cycle progresses the gradual rotation of 13gradually lowers the roller 21 so that during the ran e C increasingportions of the rotation of t e cam 10 are accompanied without anycontact between 29 and 69, thus retaining the minimum speed A but givingincreasing speed variations above A as shown by the full line curves Sin the range (3. With further progress of the spinning cycle themovement of1'3 gradually lowers the roller 21 so that during the rangeD(the bolt 29 is no longer in contact with 69 and therefore 28 travelsthe full resultant received motion, and with a gradual lowering of theroller 21 the motor speeds are represented by the curves S in the rangeD and it can be seen that the. speed variation remains constant for eachsucceeding layer of yarn although the maximum speeds areincreased.During the range E the shape of the cam 13 is such that the roller 21remains at the same elevation and thus the speed variation is constantwith each la er of yarn without any change in the maximum speed as shownby the curves S in the range E. During the final range F it.is usuallydesirableto make the shape of the cam 13 such that the roller 21 isgradually raised and thus the speed variation is constant for each layerof yarn and the maximum speeds are decreased. On completion of thespinning cycle the builder mechanism on the spinning machine is returnedto its starting osition, thus tending to slacken the cable 15 ut thetension-of the spring 17 pulls the cable back, thus also returning thecam 13 to its starting position.

Durin operation the following spinning cycle admstments are possiblewithout the interchange of parts. Adjustment of the bolt 29 limits theupward movement of 28 and hence also limits the upward movement of 37,thus determining the position of the speed line A in the region B whichin turn influences the shape of the speed curves in the region C.

Turnin the wheel 49 raises or lowers 28 and 37 whic respectivelyincreases or decreases the speed of all parts of the spinning cycleincluding the speed A equal amounts, thus changing the actual speedswithout changing the speed variation with each layer of yarn or the shae of any part of the spinning cycle. Turning t e wheel 46 does notaffect the expressed relationship between the motions of 28 and 37 butit does chan e the ratio between the motions of 28 and 3 thus alteringthe magnitude but not the characteristics of the speed variationsbrought about by the controller. By adjustment of any or all of theseadjusting devices on the controller the spinnin cycle can be readilychanged without the interchange of parts so as to operate with the idealspinning cycle with various qualities of yarn, varying degrees ofhumidity, etc.

Notwithstanding all possible care, slight variations in the motorconstruction might occur resulting in slight variations in its inertiaand its sensitiveness of speed change and in addition the inertia of thespinning machine varies with the number of bobbins, mechanicalconstruction, etc. It should therepositions of the traverse cam 10 andthe element which drives it from the traverse mechanism of the spinningmachineso as to readily secure the correctrelationship between thespeeds and the yarn osition on the bobbin necessary for the idzzalspinnin cycle. This is accomplished by the 'coup in 11 shown in Fi 4, adetail drawing of w ich is shown in i 9 in which similar parts to thoseshown in ig. 1 are represented by the same numbers. Referring to Fi 9,the couplin llconsists of two separa le parts of whic 115 represents thedriving art having a sliding fit over the shaft 12 w ich drives115'throu h the key 116 fitting into the shaft groove an the slot 117 inpart 115. The bolt 118 is threaded into 115 but does not clamp the shaft12. 119 represents a spring pressing against 115 the other end of thespring being secured to the shaft 12 and 120 represents two pinssecuredto 115. The spring 119 prevents the accidental sliding back of115. 121

represents a flange on 115. Part 115 rotates the driven part 122 throughthe pins 120 fitting into two of twelve-equally spaced holes in 122,there being a slight clearance between the holes and the pins to secureeasy entrance of the latter. The cam 10 fits snugly on the taper fit of122 and the nut 123 returns 10 in place, there being no key or otherlocking means between 10 and 122. The entire cou- 11 rotates on {the end124 of the stationa pin 125 having a hole 126 for inserting lu ricantsfor the rubbing surfaces. The relative 12' are c anged by grippingthe-flange ositions otthe cam 10 andtheahsft' I fore be possible toeasily change-the relative sliding 115 back, allowing 1'2 torotate aslight amount in the recess of 122 and then releasing 115 whereupon thespring 119 will cause the pins 120 to enter the next two diametricaloles in 122. In most cases two or three trials will give the desired camposition but if the nearest set of holes does not give the exact camposition desired the bolt 123 is loosened, the cam 10 is slightly tappedto loosen it from its taper fit and turned the desired amount and a aintightened in place by the nut 123. when the correct position of the cam10 has been secured the bolt 118 may be clamped to the shaft to preventeasy disturbance of the cam position.

Fig. 4 shows that the ositions of 29 and 34 are respectively locked by30 and 43 thus preventing movements due to vibration with 1 resultingdisturbance of the adjusted spinresults in speed changeshaving asubstan- .from the lint which ning cycle. It is equally important tolock the position of 25 in 28 but similar locking .means cannot beemployed because of the inaccessibilit to easily lock and unlock suchmeans. 'l herefore I employ the locking means shown in Fig. 10 whosedescription will be best understood when considered in connection-withFig. 6, the similar parts of both figures being represented bysimilarnumbers. In Fig. 10, a hole 127 is drilled as shown into the block 26and a spring 12'? placed into the hole forces the ball 128 against oneof the V-shaped notches in the screw 25. The usually prevailingvibration will not rotate the screw 25 against thetension of the spring127, Whereas hand movement of the knurled nut 49 in Fig. 4 will move 25and with several of these notches the screw 25' can be moved from notchto notch with very small speed changes.

The operation of my controller in conjunction with the brush shiftingdevice therefore tially constant ratio to the controller received motionand the adjusting devices on my controller enable operation with theideal spinning cycle undervarious operating conditions without theinterchange of new parts,

neither of these advantageous operating characteristics being obtainablewith any control device of which I am aware. In addition my controllerand brush shifting device may be builtwithin the motor frame and basethus saving space and protecting the mechanism prevails near textilemachinery.

I have described my invention in connection with a spinning machine whenspinning a filling wind but'it will be obvious to those skilled inthe'art that my invention is equally applicable to the. spinning of a.war wind.

I have described the operation oi my controller' with a Schrage typebrush shifting alternating current motor but it is evident that mycontroller can be used to operate any motor or other device requiring aregulating motion which is substantially proportional to that anglewhose sine is proportional to the controller received motion. I havedescribed preferred constructions of my controller and brush shiftingdevice to give proper speed control of spinning machines and the like,but it is obvious that various of a rotatable shaft, a movable memberrestricted to a linear movement," a second movable member restrlcted toa rotary movement,

motion transmitting means between said shaft and the first mentionedmovable member for transforming the rotary movement of said shaft into alinear reciprocating movement of'said first mentioned movable member,and means actuated by the first mentioned movable member for rotatingthesecond mentioned movable member through those angles whose sines aresubstantially directly proportional to the linear movement of the firstmentioned movable member.

2. In a regulating device, the combination of a plurality of rotatableshafts, a. movable member restricted to a linear movement, a secondmovable member restricted to a ro tary movement, motion transmittingmeans between said shafts and the first mentioned movable member forcombining and transforming the rotary movements of said shafts into alinear reciprocating movement of said first mentioned movable member,and means actuated by the first mentioned movable member for rotatingthe second mentioned movable member through those angles whose shaft andthe first mentioned movable member for transforming the rotary movementof said shaft into a linear reciprocating movement of said firstmentioned movable member, a. driving member adapted to move freely on asurface of the first mentioned movable member in a directionperpendicular to the plane of the linear movement of said firstmentioned movable member, and means for securing said driving member tothe sec- 0nd mentioned movable member so that both rotate at the sameangular velocity.

4. In a regulating device, the combination of a plurality of rotatableshafts, a movable member restricted to a linear movement, a secondmovable member restricted to a rotary movement, motion transmittingmeans between said shafts and the first mentioned movable member forcombining and transforming the rotary movements of said shafts into alinear reciprocatingmovement of said first mentioned movable member, adriving member adapted to move freely on a surface of the firstmentioned movable member in a direction perpendicular to the plane ofthe linear movement of said first mentioned mov 1 able member, and meansfor securing said .driving member to the second mentioned movable memberso that both rotate at the same angular velocity.

5. In a re lating device, the combination of a rotatab e shaft, amovable member restricted to a linear movement, a second mov able memberrestricted to a rotary movement, motion transmitting means between saidshaft and the first mentioned movable member for transforming the rotarymovement of said shaft into a linear reciprocating movement of saidfirst mentioned movable member, a driving member adapted to move freelyon a surface of the first mentioned movable member in a directionperpendicular to the plane of the linear movement of said firstmentioned movable member, means for securing said driving member to thesecond mentioned movable member so that the axis of the driving memberis substantially parallel to the rotation axis of the second mentionedmovable member, and means for moving said driving member to change thedisbetween its axis and the rotation axis of the second mentionedmovable member.

6. In a regulating device, the combination of a lurality of rotatableshafts, a movable mem r restricted to a-linear movement, a secondmovable member restricted to a rotary movement, motion transmittingmeans between said shafts and the first mentioned movable member forcombining and transforming the rotary movements of said shafts into alinear reciprocating movement of said first mentioned movable member, adriving member adapted to move freely on a surface of the firstmentioned movable member in a direction perpendicular to the plane ofthe linear movement of said first mentioned-movable member, means forsecuring said driving member to the second mentioned movable member sothat the axis of the driving member is substantially parallel to therotation axis of the second mentioned movable member, and means formoving said driving member to change the distance between its axis andthe rotation axis of the'second merrtioned movable member.

7. In a re ulating device, the combination of a rotatab e shaft, amovable member restricted to a linearmovement, motion transmitting meansbetween said shaft and said ing member to said gear so that both rotateat the same angular velocity, a rack in mesh with said gear, and meansfor restricting said rack to a linear movement.

8. In a regulating device, the combination of a plurality of rotatableshafts, a movable member restricted to a linear movement, motiontransmitting means between said shafts and said movable member forcombining and transforming the rotary movements of said shafts into alinear reciprocating movement of said movable member, a driving memberadapted to move freely on a surface of said movable member in adirection perpendicular to the planeof the linear movement of saidmovable member, a rotatable gear, means for securing said driving memberto said gear so that both rotate at the same angular velocity, a rack inmesh with said gear, and means for restricting said rack to a linearmovement.

9. In a regulating device, the combination of two rotatable cams, twobeams pivoted on each other, common resilient means secured to saidbeams, a projection secured to one of said beams in such a position thatthe action of said resilient means brings the other of said beamsagainst said projection, means secured to one of said beams engaging theperiphery of one of said cams, means secured to the other of said beamsengaging the periphery of the other of said cams, a block pivoted on oneof said beams, a movable member restricted to a linear movement, aconnecting member between saidblock and said movable member, a drivingmember adapted to move freely on a surface of said movable member in adirection perpendicular to the plane of the linear movement of saidmovable member, a second movable member restricted to a rotary movement,and means for secured to the other of said beams engaging the peripheryof the other of said cams, a block pivoted on one of said beams, amovable member restricted to a linear movement, a connecting memberbetween said block and said movable member, a driving member adapted tomove freely on a surface of said movable member in a directionperpendicular to the plane of the linear movement of said movablemember, a second movable member restricted to a rotarymovement, meansfor securing said driving member to the second mentioned movable memberso that the axis of the driving member is substantially parallel to therotation axis of the second mentioned movable member, and means formoving said driving member to change the dis tance between its axis andthe rotation axis of the second ment 'oned movable member.

11. In a regulating device, the combination of two rotatable cams, twobeams pivoted on each other, common resilient means secured to saidbeams, a projection secured to one of said beams in such a position thatthe action. of said resilient means brings the other of said beamsagainst said projections, means secured to one of said beams engagingthe periphery of one of said cams, means secured to the other of saidbeams engaging the periphery of the other of said cams, a block pivotedonone of said beams, a movable member restricted to a linear movement, aconnecting member between'said'block andsaid movable member, a drivingmember adapted to move freely on a surface of saidmovable member in adirection perpendicular to the plane of the linear movement of saidmovable member, a rotatable gear, means for securing said driving memberto said gear so that bot rotate at the same angular velocity, a rack inmesh with said gear, and means for restricting said rack to a linearmovement.

12. In a regulating device, the combination of a rotatable shaft, amovable member restricted to a linear movement, motion transmittlngmeans between sald shaft and said movable member for transforming therotary movement of said shaft into a linear reciprocating movement ofsaid movable member, a

rotatable gear, a block resting against one face of said gear, a drivingmember secured to said block, said driving member being adapted to movefreely on a surface of said movable member in a directionperpendicularto the plane of the linear movement of said movable member,means for sliding said block relative to said gear to change thedistance between the center of said driving member and the rotation axisof said gear, and means for securing said block to said gear so thatboth rotate as a unit.

13. In a regulating device, the combination of a rotatable cam, apivoted beam carrying a roller engaging the periphery of said cam, ablock pivoted on said eam,said blockhaving lar to an aperture, a movablemember restricted to a linear movement, a second movable memberrestricted to a rotary movement, a threaded member screwed into thefirst mentioned movable member and protruding through said aperture, ashoulder secured to saidthreaded member and resting on said block, agear secured to said shoulder, means for rotating said gear, a drivingmember adapted to move freely on a surface of the first mentionedmovable member in a direction perpendicuthe plane of the linear movementof said first mentioned movable member, and means for securing saiddriving member to 'the' second mentioned movable member so that bothrotate at the same angular velocity. 14. In a regulating device, thecombination of two rotatable cams, two beams pivoted on each other,common resilient means secured to said beams, a projection secured toone of said beams in such a position that the action of said resilientmeans brings the other of said beams against-said projection, meanssecured to one of saidbeams engaging the periphery of one of said cams,means secured to the other of said beams engaging the periphery of theother of said cams, a block pivoted on one of said beams, a stationarymember in spaced relationship to said block, and means carried by saidblock and adapted to come into contact with said stationary member at apredetermined distance between said block and said stationary member toprevent further movement of said block toward said stationary member.

15. In a regulating device, the combination of a pin having two spacedapart shoulders, a rotatable circular sleeve located on said pin betweenits shoulders with a small axial clearance between the ends of thesleeve and the shoulders, said sleeve being threaded on its outercircular surface, a handle secured to said sleeve, an internallythreaded member screwed on said sleeve in spaced relationship to saidhandle, a block secured to a surface of said internally threaded member,a second block adapted to slide on the first mentioned block withoppositely disposed surfaces of the second mentioned block respectivelyproximate to a surface of said handle and said surface of saidinternally threaded member, and means for moving the second mentionedblock relatively to the first mentioned block.

16. In a brush shifting device for a dynamo electric machine, thecombination of a stationary member providedwith a shoulder and acircular surface extending from the shoulder to the end of said member,at least one brush yoke adapted to rotate on said circular surface, thelength of said circular surface from the shoulder to the end .ofsaidmember being-such that the hub of a brush 17. In a brush shifting devicefor a dynamo electric machine, the combination of two movable brushyokes, a member having a circular surface, a shifting yoke adapted tomove radially and angularly on said circular, surface, engaging meansbetween said brush yokes and said shifting yoke adapted to move saidbrush yokes during'movement of said shifting yoke, a stationary cam, andmeans secured to one end of said shifting yoke adapted to engage thecontour of said cam for uiding said end of the shifting yoke inaccordance with said cam cont-our.

' 18. In a brush shifting device for a dynamo electric machine, thecombination of two movable brush yokes, a member having a circularsurface, a shifting yoke adapted to move radially and angularly on saidcircular surface, two driving pins with corresponding driving lugssecured to said yokes on oppositesides of said circular surface andadapted to move said brush yokes during movement of said shifting yoke,a cam having two offset sections connected bya substantially circularsection, one end of said shifting yoke adapted to enage the contour ofsaid cam for guiding said end of the shifting yoke in accordance withsaid cam contour, and means for removably securing said cam in either oftwo predeterminedpositions, one of' said positions being so selectedthat the vertical axes of the offset sections of said cam aresubstantially radial with respect to the center of said circular surfaceand the circular section of said cam is the arc of a circle whose radiusis the center of one of said pins when said end of the shifting yokeisguided in accordance with the contour of the circular section of saidcam, and the other of said positions being so selected that the verticalaxes of the offset sections of said cam are substantially radial withrespect to the center of said circular surface and the circular sectionof said cam is the arc of a circle whose radius is the center of theother of said pins when said end of the shifting yoke is guided inaccordance with the contour of the circular section of said cam.

19. In combination, a dynamo electric machine comprising a primarywinding, two movable brush yokes, a member having a circular surface, ashifting yoke adapted to move radially and angularly on said circularsurface, engaging means between said brush yokes and said shifting yokeadapted to move said brush yokes during movement of said shifting yoke,a stationary cam removably secured in either of two predeterminedposimeans secured totions, means secured to one end of said shiftingyoke adapted to engage the contour of said cam for guiding said end ofthe shifting yoke in accordance with said cam contour, a source ofalternating current, a switch for connecting said primary winding tosaid source to cause rotation of said machine in one direction, a switchfor connecting said primary winding to said source to cause rotation ofsaid machine in the opposite direction, means responsive to apredetermined position of one of said brush yokes with said cam in oneof its predetermined positions for effecting the closing of the firstmentioned switch, means responsive to a predetermined position of theother of said brush yokes with said cam in the other of itspredetermined positions for effecting the closing of the other of saidswitches, and means for moving said shifting yoke to bring therespective brush yoke to its predetermined position with said camsecured in predetermined positions.

20; A brush shifting device for a dynamo electric machine comprising twomovable brush yokes, a member having a circular surface, a shifting yokeadapted to move radially and angularl on said circular surface, engagingmeans etween said brush yokes and said shifting yoke adapted to movesaid brush yokes during movement of the shifting yoke, a stationary cam,means secured to one end of said shifting yoke adapted to engage thecontour of said cam for guiding said end of the shifting yokejinaccordance with said cam contour, a rotatable shaft, a movable memberrestricted to a linear movement, motion transmitting means between saidshaft and said movable member for transforming the rotary movementof'said shaft into a linear reciprocating movement of said movablemember, a rotatable gear, means actuated by said gear through thoseangles whose sines are substantially directly proportional to the linearmovement of said movable member, a rack in mesh with said gear, one endof said rack being adapted to impart its, movement to the other end ofsaid shifting yoke, and means for restricting said rack to a linearmovement.

21. A brush shifting device for a dynamo electric machine comprising twomovable brush yokes, a member having a circular surface, a shifting yokeadapted to move radially and angularly on said circular surface,engaging means between said brush yokes and said shifting yoke adaptedto move said brush yokes during movement of the shifting yoke, astationary cam, means secured to either of its two said movable memberfor rotating one end of said shifting yoke adapted to en- V gage thecontour of said cam for guiding said end of the shifting yoke inaccordance with said cam contour, a plurality of rotatable shafts, amovable member restricted to a I ber f 1 rotarymovements of said shaftsinto a linear movement, motion transmittin means between said shafts andsaid movab e memor combining and transforming the inear reciprocatingmovement of said movable member, a rotatable gear, means actuated bysaid movable member for rotating said gear through those angles whosesines are substantially directly proportional to the linear moven 2nt ofsaid movable member, a rack in mesh with said gear, one end of said rackbeing adapted to impart its movement to the other end of said shiftingyoke, and means for restricting said rack to a linear movement.

22. A brush shifting device for a dynamo electric machine comprising twomovable brush yokes, a member having a circular surface, a shifting yokeadapted to move radi ally and angularlyon said circular surface,engaging means between said brush yokes and said shifting yoke adaptedto move said brush yokes during movement of the shifting yoke, astationary cam, means secured to one end of said shifting yoke adaptedto engage the contour of said camfor guiding said end of the shiftingyoke in accordance with said cam contou-r, two rotatable cams, two beamspivoted on each other, common resilient means secured to said beams, aprojection secured to oneof said beams in such a position that theaction of said resilient means brings the other of said beams againstsaid projection, means secured to one of said beams engaging theperiphery of one of said rotatable cams, means secured to the other ofsaid beams engaging the periphery of the other of said rotatable cams, ablock pivoted on one of said beams, a movable member restricted to alinear movement, a connecting member between said pivoted block and saidmovable member, a driving member adapted to move freely on a surface ofsaid movable member in a direction perpendicular to the plane of thelinear movement of said movable member, a rotatable gear, means forsecuring said driving member to said gear so the same angular velocity,a rack in mesh with said gear, one end of said rack being adapted toimpart its movement to the other end of said shifting yoke,

' and means for restricting said rack to a linear movement.

23. A brush shifting device for a dynamo electric machine comprising twomovable brush yokes, amember provided with a circular surface, astationary projection, a shifting yoke adapted to move radially andanguyoke adapted to move said lady on said circular surface, engagingmeans between said brush yokes and'said shifting brush yokes duringmovement of said shifting yoke, 'a stationary cam, means secured to oneend of said shifting yoke adapted to engage the contour. of said cam forguiding said end of-the shifttwo rotatable cams, two beams pivoted oneach other, common resilient means secured to said beams, 'a projectionsecured to one of said beams in such a position that the action of saidresilient means brings the other ofsaid beams against the last mentionedprojection, means secured to one of said beams engaging the periphery ofone of said rotatable cams, means secured to the other of said beamsengaging the periphery of the other of said rotatable cams, a blockpivoted on one of said beams, a movable member restricted to a. linearmovement, a connecting member between said pivotedblock and said movablemember, means carried by said pivoted block adapted to come into contactwith said stationary projection at a predetermined distance between saidblock and said stationary projection to prevent further movement of saidblock toward said stationary projection,

a driving member ada ted to move freel on a surface of said mova lemember in a direction perpendicular to the plane of the linear movementof said movable member, a rotatable gear, means for securing saiddriving member to said gear so that both rotate at the same angularvelocity, a rack in mesh with said gear, one end of said rack beingadapted to impart its movement to the other end of said shlfting yoke,and 'means for restricting said rack to a linear movement.

24. A. brush shifting device for a dynamo electric machine comprisingtwo movable brush yokes, a member having a circular surface, a shiftingyoke adapted to move radially and angularly on said circular surface,engaging means between saidbrush yokes and said shifting yoke adapted tomove said brush yokes during movement of the shifting yoke,

a stationary cam, means secured to one end 7 of said shifting yokeadapted to engage the contour of said cam for guiding said end of theshifting yoke in accordance with said cam contour, two rotatable cams, amovable member restricted to a linear movement, motion transmittingmeans between said rotatable;

surface of said gear, a driving member se-- cured to said block,saiddriving member be ing adapted to move freely on a surface of saidmovable member inf'a direction perpendicular to the plane of the linearmovement of said movable member, means for slidingsaid block relativelyto said gear to change the distance between the axis of said drivingmember and the rotation axis of said gear,

means for securing said block to'said ar so that both rotate as a unitamok in mes with said gear, one end of said rack being adapted to impartits movement to the other end of V shifting yoke adapted said shiftingyoke, and means for restricting said rack to a linear movement. 25. Abrush shifting device for a dynamo electric machine comprising twomovable 8 brush yokes, a member provided with a circular surface, astationary projection, a shifting yoke adapted to move radially andangularly on said circular surface, engaging means between said brushyoks and said to move said brush yokes during movement of said shiftingyoke, a stationar cam, means secured to one end of said shi ing yokeadapted to engage the contour of said cam for uiding said end of 1B theshifting yoke in accor ance with said cam contour, two rotatable cams,two beams pivoted on each other, common resilent means secured to saidbeams,'a-projection secured to one of said beams in such a position thatthe action of said resilient means brings the other of said beamsagainst the last mentioned projection, means secured to one of saidbeams engaging the periphery of one of said rotatable cams,means'secured to the other of said beams engaging the periphery of theother of said rotatable cams, a block pivoted on one of said beams, amovable member restricted to a linear movement, a threaded memberconnecting said pivoted block and 80 said movable member, said threadedmember being so connected to said pivoted block and said movable memberthat the rotation of said threaded member changes the distance betweensaid pivoted block and said movable member, means for rotating saidthreaded member, means carried by said pivoted block adapted tocome intocontact with said stationaryprojection at a predetermined distancebetween said block and said stationary projection to prevent furthermovement of said block toward said stationary projection, a rotatablegear, a block resting against one 7 surface of said gear, a drivingmember secured to the last mentioned block, said drivingY member beingadapted to move freely on a surface of said movable member in adirection perpendicular to the plane of the linear movement of saidmovable member, means for sliding the last mentioned block relatively tosaid gear to change the distance between the axis of the driving memberand the rotation axis of said gear, means for securing the lastmentioned block to said gear so that both rotate as a unit, a'rack inmesh with said gear, one end of said rack being adapted to impart itsmovement to the other end of said shifting yoke, and means forrestricting said rack to a linear movement.

26. A brush shifting device for a dynamo 00 electric machine comprisingtwo movable b ush yokes, a member provided with a circular surface, astationary projection, a shifting yoke adapted to move radially andangularly on said circular surface, engaging as means between said brushyokes and said resilient means secured to said beams, a procontour ofsaid cam for guiding said end of the shifting yoke in accordance withsaid cam contour, two rotatable cams, means for rotating one of saidrotatable cams, a shaft secured to the other rotatable cam, a flangedmember secured to said shaft, a second shaft, a flanged member adaptedto slide longitudinally on the second shaft, engaging means between saidflanged members adapted to en-5 gage each other at a plurality ofrelative angular positions of said flanged members, resilient means forbiasing the slidable flanged member toward the other flanged member, Itwo beams. pivoted on each other, common 7 jection secured to one ofsaid beams in such a position that the action of said resilient meansbrings the other of said beams against the last mentioned projection, aroller secured to one of said beams engaging the periphery of one ofsaid rotatable cams, a roller secured to the other of said beamsengaging the periphery of the other of said rotatable cams, a blockpivoted on one of said beams, said block having an aperture, a movablemember restricted to a linear movement, a threaded 9 member screwed intosaid movable member and protruding through said aperture, a shouldersecured to said threaded member and resting on said pivoted block, meansfor rotating said threaded member, means carried bysaid pivoted blockadapted to come into contact with said stationary projection at apredetermined distance between said pivoted block and saidstationaryprojection to prevent further movement of said pivoted block toward saidstationary projection, a r0- tatable gear, a block resting against onesurface of said gear, a driving member secured to the last mentionedblock, said driving member being adapted to move freely on a surface ofsaid movable member in a direction perpendicular to the plane of thelinear movement of said movable member, means for sliding the lastmentioned block relatively to said gear to change the distance betweenthe axis of the driving member and the rotation axis of said gear, meansfor securing the last mentioned block'to said gear so that both rotateas a unit, a rack in mesh with said gear, one end of said rack beingadapted to impart its movement to the other end of said shifting yoke,

. and means for restricting said rack to a linear movement.

In witness whereof, I have hereunto set my hand this 16th day of May,1930.

J OHN I. HULL.

CERTIFICATE OF CORRECTION. 15

Patent No. 1,860,183. May 24, 1932.

JOHN l. HULL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 1,line 86, strike out the word "ring" and insert the same before "rail" insame line; page 5, line 71, for the misspelled word "spining" readspinning, and line 106, for "examinating" read examining; page 6, line101, for "regulations" read regulation; page 11, line 26, claim 11, for"projections" read projection; and that the said Letters Patent shouldbe read with these corrections therein that the same may conform to therecord of the case in the Patent Office.

Signed and sealed this 12th day of July, A. D. 1932.

M. J. Moore, (Seai) Acting Commissioner of Patents.

